110 WITHERITE. Witherite is composed of barium carbonate, (BaC0 3 ). It is usually found as a vein mineral or filling cavities in rocks. There is none produced in Canada. USES. The only use, according to the knowledge of the writer, to which this mineral is put in Canada is in the enamelling of metal ware. The finely ground material is mixed with other substances, applied to the metal, and then heated to the point of fusion. In the manufacturing of chemicals, witherite is frequently used as a source of barium for barium compounds; for example, in the preparation of the barium peroxide used in making hydro gen peroxide (H 2 0 2 ). It is used in some countries in the refining of beet sugar, but this use is decreasing. Amount of witherite used in the manufacturing industries, as reported by the consumers:— Location No. of firms reporting consumption Domestic Imported Tons Tons 2 90 British Columbia — — — Canada (Total) 2 — 90